diff --git a/psyncPC.iml b/psyncPC.iml
index e9ee694..0080e24 100644
--- a/psyncPC.iml
+++ b/psyncPC.iml
@@ -1,13 +1,16 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<module version="4">
-  <component name="NewModuleRootManager" inherit-compiler-output="true">
-    <exclude-output />
+<module org.jetbrains.idea.maven.project.MavenProjectsManager.isMavenModule="true" type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" LANGUAGE_LEVEL="JDK_1_7">
+    <output url="file://$MODULE_DIR$/target/classes" />
+    <output-test url="file://$MODULE_DIR$/target/test-classes" />
     <content url="file://$MODULE_DIR$">
       <sourceFolder url="file://$MODULE_DIR$/src/main/java" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/java" isTestSource="true" />
+      <excludeFolder url="file://$MODULE_DIR$/target" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
-    <orderEntry type="library" name="Maven: com.google.code.gson:gson:2.6.2" level="project" />
     <orderEntry type="library" scope="TEST" name="Maven: junit:junit:3.8.1" level="project" />
+    <orderEntry type="library" name="Maven: com.google.code.gson:gson:2.6.2" level="project" />
   </component>
 </module>
\ No newline at end of file
diff --git a/src/main/java/bishakh/psync/Discoverer.java b/src/main/java/bishakh/psync/Discoverer.java
index 15ba2fa..03128cb 100644
--- a/src/main/java/bishakh/psync/Discoverer.java
+++ b/src/main/java/bishakh/psync/Discoverer.java
@@ -9,6 +9,10 @@
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.concurrent.ConcurrentHashMap;
+import java.io.*;
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.*;
 
 
 /**
@@ -16,10 +20,17 @@
  */
 public class Discoverer {
 
+    HashMap<String,String>contactMap = new HashMap<>(); /* Store contact information */
+
     String BROADCAST_IP;
+    final String DATABASE_NAME;
+    final String DATABASE_PATH;
+
+
     int PORT;
     String PEER_ID;
     Logger logger;
+    File file;      /* File attribute added */
     final Thread[] thread = new Thread[3];
     final BroadcastThread broadcastThread;
     final ListenThread listenThread;
@@ -31,11 +42,20 @@ public class Discoverer {
     public volatile ConcurrentHashMap<String, ArrayList<String>> priorityPeerList;
     public volatile ConcurrentHashMap<String, ArrayList<String>> originalPeerList;
 
-    public Discoverer(String BROADCAST_IP, String PEER_ID, int PORT, Logger LoggerObj) {
+    public Discoverer(String BROADCAST_IP, String PEER_ID, int PORT, Logger LoggerObj,String fileName,String databaseDirectory ) throws IOException {
         this.BROADCAST_IP = BROADCAST_IP;
         this.PORT = PORT;
         this.PEER_ID = PEER_ID;
         this.logger = LoggerObj;
+        this.DATABASE_NAME = fileName;
+        this.DATABASE_PATH = databaseDirectory+DATABASE_NAME;
+        this.file = new File(DATABASE_PATH);
+
+        if(!file.exists())
+        {
+           file.createNewFile();
+        }
+
 
         // Initialize priorities (lower int = higher priority)
         // The peers whose ID starts with these keywords will have the priority
@@ -58,6 +78,7 @@ public Discoverer(String BROADCAST_IP, String PEER_ID, int PORT, Logger LoggerOb
         thread[0] = new Thread(broadcastThread);
         thread[1] = new Thread(listenThread);
         thread[2] = new Thread(peerExpiryThread);
+
     }
 
     public void startBroadcast(){
@@ -113,7 +134,24 @@ public void stopPeerExpiry() {
         }
     }
 
-    public void startDiscoverer(){
+    public void startDiscoverer() throws FileNotFoundException {
+        /*when discoverer starts, previous information in contactHistory.txt gets stored in HashMap "contactMap" */
+        FileReader fileReader =  new FileReader(file);
+        BufferedReader bufferedReader = new BufferedReader(fileReader);
+        try {
+            String line =bufferedReader.readLine();
+            while(line!=null)
+            {
+                String[] one=line.split(" ",100); /// here length of PEER_ID is restricted
+                contactMap.put(one[0],one[1]);
+                line=bufferedReader.readLine();
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        PrintWriter writer = new PrintWriter(file);
+        writer.print("");
+        writer.close();
         startBroadcast();
         startListener();
         startPeerExpiry();
@@ -287,6 +325,25 @@ public void run() {
                     if(willUpdatePeer) {
                         String peerID = new String(datagramPacket.getData(), 0, datagramPacket.getLength());
                         updatePeers(datagramPacket.getAddress().getHostAddress(), peerID);
+
+                        /* While listening to a device, everytime contactHistory.txt file is updated*/
+
+                        DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd-HH:mm:ss");
+                        Calendar cal = Calendar.getInstance();
+                        String timeStamp = dateFormat.format(cal.getTime());
+                        contactMap.put(peerID, timeStamp);
+                        FileWriter fileWriter = new FileWriter(file.getAbsoluteFile(), true);
+                        BufferedWriter bufferedWriter = new BufferedWriter(fileWriter);
+                        PrintWriter printWriter = new PrintWriter(bufferedWriter);
+                        PrintWriter writer = new PrintWriter(file);
+                        writer.print("");
+                        writer.close();
+                        for(Map.Entry m:contactMap.entrySet())
+                        {
+                            printWriter.println(m.getKey()+" "+m.getValue());
+                        }
+                        printWriter.close();
+
                     }
                 } // end of while
             }catch (UnknownHostException e){
@@ -382,4 +439,5 @@ public void stop() {
     }
 
 
-}
\ No newline at end of file
+
+}
diff --git a/src/main/java/bishakh/psync/SyncService.java b/src/main/java/bishakh/psync/SyncService.java
index 9920fb5..36413bc 100644
--- a/src/main/java/bishakh/psync/SyncService.java
+++ b/src/main/java/bishakh/psync/SyncService.java
@@ -5,6 +5,7 @@
 import java.text.SimpleDateFormat;
 import java.util.Calendar;
 
+
 public class SyncService {
 
     private static final String BROADCAST_IP = "172.16.5.255";
@@ -17,6 +18,8 @@ public class SyncService {
     private static String mapFileServerDirectory = "/home/alarm/DMS/";
     private static String databaseAndLogDirectory = "/home/alarm/DMS/";
     private static String databaseName = "fileDB.txt";
+    private static String contactName ="contactHistoryFile.txt";
+
 
     public Logger logger;
     public WebServer webServer;
@@ -24,62 +27,73 @@ public class SyncService {
     public FileManager fileManager;
     public FileTransporter fileTransporter;
     public Controller controller;
+   
+
+    public SyncService() throws IOException {
+
 
-    public SyncService() {
         logger = new Logger(databaseAndLogDirectory, PEER_ID);
-        discoverer = new Discoverer(BROADCAST_IP, PEER_ID, PORT, logger);
+        discoverer = new Discoverer(BROADCAST_IP, PEER_ID, PORT, logger,contactName,databaseAndLogDirectory);
         fileManager = new FileManager(PEER_ID, databaseName, databaseAndLogDirectory, syncDirectory, mapFileServerDirectory, logger);
         fileTransporter = new FileTransporter(syncDirectory, logger);
         controller = new Controller(discoverer, fileManager, fileTransporter, syncInterval, maxRunningDownloads, logger, 2, true);
         webServer = new WebServer(8080, controller, logger);
+
     }
 
 
-    public SyncService(String inputPeerId, String baseDirectory) {
-        syncDirectory = baseDirectory + File.separator + "sync" + File.separator;
+    public SyncService(String inputPeerId, String baseDirectory) throws IOException {
+        syncDirectory = baseDirectory  + "sync" + File.separator;
         mapFileServerDirectory = baseDirectory;
         databaseAndLogDirectory = baseDirectory;
         PEER_ID = inputPeerId;
 
+
         logger = new Logger(databaseAndLogDirectory, PEER_ID);
-        discoverer = new Discoverer(BROADCAST_IP, PEER_ID, PORT, logger);
+        discoverer = new Discoverer(BROADCAST_IP, PEER_ID, PORT, logger,contactName,databaseAndLogDirectory);
         fileManager = new FileManager(PEER_ID, databaseName, databaseAndLogDirectory, syncDirectory, mapFileServerDirectory, logger);
         fileTransporter = new FileTransporter(syncDirectory, logger);
         controller = new Controller(discoverer, fileManager, fileTransporter, syncInterval, maxRunningDownloads, logger, 2, true);
         webServer = new WebServer(8080, controller, logger);
     }
 
-    public SyncService(String inputPeerId, String baseDirectory, int priorityMethod) {
-        syncDirectory = baseDirectory + File.separator + "sync" + File.separator;
+    public SyncService(String inputPeerId, String baseDirectory, int priorityMethod) throws IOException {
+        syncDirectory = baseDirectory +"sync" + File.separator;
         mapFileServerDirectory = baseDirectory;
         databaseAndLogDirectory = baseDirectory;
         PEER_ID = inputPeerId;
 
+
         logger = new Logger(databaseAndLogDirectory, PEER_ID);
-        discoverer = new Discoverer(BROADCAST_IP, PEER_ID, PORT, logger);
+        discoverer = new Discoverer(BROADCAST_IP, PEER_ID, PORT, logger,contactName,databaseAndLogDirectory);
         fileManager = new FileManager(PEER_ID, databaseName, databaseAndLogDirectory, syncDirectory, mapFileServerDirectory, logger);
         fileTransporter = new FileTransporter(syncDirectory, logger);
         controller = new Controller(discoverer, fileManager, fileTransporter, syncInterval, maxRunningDownloads, logger, priorityMethod, true);
         webServer = new WebServer(8080, controller, logger);
     }
 
-    public SyncService(String inputPeerId, String baseDirectory, int priorityMethod, boolean restrictedEpidemicFlag) {
-        syncDirectory = baseDirectory + File.separator + "sync" + File.separator;
+    public SyncService(String inputPeerId, String baseDirectory, int priorityMethod, boolean restrictedEpidemicFlag) throws IOException {
+
+
+        syncDirectory = baseDirectory + "sync" + File.separator;
         mapFileServerDirectory = baseDirectory;
         databaseAndLogDirectory = baseDirectory;
         PEER_ID = inputPeerId;
-
         logger = new Logger(databaseAndLogDirectory, PEER_ID);
-        discoverer = new Discoverer(BROADCAST_IP, PEER_ID, PORT, logger);
+        discoverer = new Discoverer(BROADCAST_IP, PEER_ID, PORT, logger,contactName,databaseAndLogDirectory);
         fileManager = new FileManager(PEER_ID, databaseName, databaseAndLogDirectory, syncDirectory, mapFileServerDirectory, logger);
         fileTransporter = new FileTransporter(syncDirectory, logger);
         controller = new Controller(discoverer, fileManager, fileTransporter, syncInterval, maxRunningDownloads, logger, priorityMethod, restrictedEpidemicFlag);
         webServer = new WebServer(8080, controller, logger);
+
     }
 
 
 
-    public  void start(){
+    public  void start() throws FileNotFoundException {
+
+        
+
         discoverer.startDiscoverer();
         fileManager.startFileManager();
         controller.startController();
@@ -97,7 +111,7 @@ public void stop() {
         webServer.stop();
     }
 
-    public static void main(final String[] args) {
+    public static void main(final String[] args) throws IOException {
         System.out.println(args.length);
         if(args.length < 2){
             SyncService s = new SyncService();
@@ -147,6 +161,8 @@ public void uncaughtException(Thread t, Throwable e) {
                 }
             }
         });
+
+
     }
 
 }